Vapor electric device



2 .Sheets-Sheet 1 m, n fm 5 fn.

J. H. COX

VAPOR ELECTRIC DEVICE Filed Sept. 4, 1941 Nov. 2, 1943.

Nov. 2, 1943. J. H.. cox

VAPOR ELECTRIC DEVICE 2 Sheets-Sheet 2 Filed Sept. 4, V1941 x.. my, -b w, f

TNESSES: @i

f/f www y ATTORNEY Patented Nov. 2, 1943 varon 'ELECTRICI D Evloa i Joseph H. Cox, Forest Hills, Pa., assigner to West# i inghouse Electrds -Mamlfacturng Competing-. Y East Pittsburgh,P a.,-a corporation of Pennsy1-- invention relates to a'va'po'r electric device and, particularly, tov an' anode vand shield asl sembly for such a device. y

rIfhis application is` a continuation-impart of my application fseriai No5 2 sfiaosa flied 12, Y

1940 A. "In the operation of vapor electricdevcesgft tween the anode and the active cathode'surface so that the anode is ioptiallyobscured from the active cathode area, a reduction of arc backs is normally secured. However, this `s hieldsometimes increases the pickup' voltagenecessary to. f x

establish the current 'carrying arc betweenl the'Vl anode and the cathode soVA that it desirable to provide suitable passages ywhereby *at least a small amountof cathode vapor pass-intothe' i vicinity'of the anode. f"

Ceitain experiments have 'demonstrated that the condensing efficiency ofthe cooled condensing surface for condensing mercury vaporl is Imate? rially improved if the condensing'surface is" bathed by` the arc plasma in' the converter.

The anode landshield assembly according" to`V my invention is arranged to secure the *benefit of thesef'and other operating conditions.

having 'a substantially cylindrical base portion and sloping sideslv converging toward; a tip fof" less crosssectional area thannthe base. The* anode is substantially enclosed -by a shield niembe'r'fwhich conforms generally in shape to'the anode, the end -ofthe shieldiinfproximity to the anode is` substantiaily5 closed to y prevent thel blast of highly ionized cathodevapor fromen- `J tering- `the-anode space, but is provided with suitable baiiled openings to admit sufficient vapor to facilitate the pickup of the current carrying arc between the cathode and anode.

The shield is provided with arcv passages on the side portions so that the sides of the anode become the active anode face, so` that the arc flowing from the side of the anode passes adjacent the side walls of the device and the arc plasma bathes the condensing surface improving its condensing eciency. 'I'he converging shield also provides an enlarged space to facilitate the iiow of the highly ionized cathode blast to .the condensing surface.

It is an object of myinvention to provide a converter in which the anode is suitably shaped to provide a large working surface, and which is provided with a-suitable shield to exclude a major portion of the highly ionized vapor emanating from the cathode and to provide such formations that the are plasma will sweep sojav cent the condensing surfaces, and' thus improve the operatingv characteristic of the converter; 'Other objects and advantages of my invention 'will be apparent from the following"detailed`r description takenf'in conjunction with comp'anying drawings, in which:

ligurel 1- is a sectional elevation vof avapor ciectricjdevice according to myl invention; and" Fig. 2 is asimilar view of a preferred struction according to 'myinvention 'I he vaporelectric device accordingfto my inventionA comprises a suitable container" herein` illustrated 'as anietallic vessel Il In the bottom of the vessel II is a suitable pool 2 of a v apo'rizabie reconstructing cathode material,y such; as mer-A cury, or mercury amalgam. In order torestrict the active cathode farefa'S toa'predetermihed portion ofthe'f cathodopol 2. a'suitable barrier Il; usually a quartzy ring; is'anchored by suitable'- means to the Icmtto'niV of the cathode c'ontainer. `In" order toy initiate the cathode spot; a makealive" device E isfpositioned in contactwiththe active cathode surface 3l 'of cathode 2.- A suitable "25" leadin connection '1 is carried throughthewall of the container I b yfmeans of aninsulating bushing 8J "Coperatinswiih the etiche 21s an anvdwfjpreferably of graphite suspende'dion' a' suitable anode stem `I I 'which -is heldin insulatedrela- .tionto the container I by means of a suitable insulating bushing f I2." In o rder to provide largeieifective working surface, the anode liiis provided with aisubstantiallycylindrical base I3 and a tip portion I vPof substantiallyfrusto-coniev c cal or tapering 'cro'sshsection converging in 'the' At least that por` tion of the stem Il which is in Contact With the direction of the cathode 2.

anode I0 is constructed of a conducting material which .is not dissolved by hot carbon.

A shield member I5, preferably composed 10fty graphite, is suspended in insulated relation tok the anode I0 and the container I by means of suitable insulating studs I6. The shield member I5 preferably conforms substantially'in shape to the shape of the'anode II) and is placed asclose thereto as is mechanically convenient. The converging portion of the shield enclosing `the tip I Li of the anode I0 provides a tapered Vapor space I'I `through which the blast of highly `ionized. vapor.

from the cathode 2 may pass in traveling from the cathode to the condensing surface with a minimum increase in vapor pressure.l The side l portions of the shieldare provided with suitable arc passages I8. I'he passages I S are preferably acl active cathode area 3 through the arc passages i I8. As the arc passages I8 are substantially lateral of the Working face of the anode I0, the

current carrying arc passing between the cathode 3 and anode I0 sweeps adjacent the condensing surfaces so that the condensing surface is bathed in the arc plasma, thereby greatly increasing its efliciency.

vThat portion I9 of the shield I 5 in proximity to 1 y the cathode 3 is substantially closed, but in order to admit suilicient cathode vapor to allow easy i pickup of the current carryingV arc, ajsuitable opening is made in the end I9 of the shield I5 and a suitable baiiieZI provided in spaced rela- In the operation of rectiiiers, it is found that the parts directly in contact with vthe arc stream operate at a temperature of the order of 1000 C. and as iron, many iron alloysA and other metals have the property of dissolving in `carbon at this temperature, considerable dimculty has been experienced in properly securing together the various graphite parts comprising-'an anode shield. Of the base metals, copper and nickel have the property of withstanding the dissolving activity of `hot carbon. Copper is undesirable in the portions of the converter having a high mercury content such as the region traversed by the cathtion to the opening 20 so that no part of the'anode I0 is optically exposed to the active cathodev area'3 through the vapor passage 20.

ode vapor blast, therefore I have heretofore used f l screws 26-of nickel to secure` the bale 2I to theV end kI9 of the shield. Y

The nickel,however, is sputteredaway by the arc` so that not only is the fastening made insecure, but in certain application's having a high load factor the sputtered nickel contaminates the make-alive electrodes and interferes with the` normal operation of the device. VTherefore, rI

prefer to utilize a construction havingno ymetal parts exposed to the arc stream as shown in the modication according to Figr2. y y

In the preferred construction, the vapor passages in the end I9 of the shield I5 are constructed in the intact shield material. yI prefer to constructfthe passages by making a recess 30 then machining or under-cutting to form an enlarged base 3| in the recess and drilling a pluralityl of ,f holes 32V offset Withrelation in the recess 30, the size of the holes 32 anddepth of the oiset being of such proportions that no part of the anode II)` is directly exposed to the 'active cathode area 3 through the openings 30:-3I-32.

Preferably the closed end portion I9 of the shield I 5 is of such size with respect to the active cathode area 3 and the slope of the tapered side of the shield I5, that the blast of highly ionized vapor does not impinge on the openings I8 but sweeps past to the condensing surface through the enlarged space II without materially increasing the vapor pressure at any point in the device.

'Ihe tapered space I'I alsoprovides an arc space increasing in cross-sectional area in the direction of the cathode which permits the passing of the arc without crowding.

If desired, a suitable connection 22 may be made tofthe shield/I5 and carried through the ycontainer wall bymeans of an insulating bushing 23.

Preferably, liquid cooling devices, such as coolingcoils 2,4,rare provided for the condensing surface or any other portion of the device which it is desired to cool. In order to improve the appearancejofg-the deviceasuitable jacket 2571sap# plied to cover up thecooling coils 24 or'other ir- 1 regular surfaces of the device. Y

v While forpurposes of illustration have shown l and described aspeciiic embodiment oflmy in,

vention,v it will be' apparent that changes and modiiications can; be made therein without departingfrom` the true spirit of myinvention or the scope of the appended claims.

l I claim as my invention: i

1. vA' mercury vapor-valve comprising a container,y a. mercury cathode in said container,

means .for initiatingfa cathode rspot on said cathg ode, means for determining vtheactive cathode areaja streamlined anode supported in spaced relationto the cathode, a graphite shield enclosing said anode and conforming in shape thereto for providing an arc passage increasing in cross-sec.- tional areawin thedirection of thecathodefa pluralityof arc passagesin the sides of said shield wherebyI the arc plasma is brought into proximity v with alarg'efportiony of the container wall, an

opening mths e'ridcf the shieid at a point ex posed tothe cathode and a. baille-covering said perlng- M 2. Inga vaporelectric tdevice, an anode and shield assembly comprisingan anode head `having ya substantially cylindrical vbase portion, and asubstantially irusto-conicalftip portion,v a

graphiterv shield spaced from and substantially conforming in shape to the anode, a plurality of arc Apassages Vin ysaidgshield in proximity. to the sides of the anode, v`'an opening inthe end of the shield inl proximityto the end of the anode and aA baiiie covering vsaid opening.

V JOSEPHH. COX. 

